Select all that are TRUE.

Select one or more:

a. Matrix-matrix multiplication is commutative, AB=BAAB=BA

b. Matrix-matrix multiplication can be commutative, AB=BAAB=BA, for some matrices A and B

c. Matrix product ABAB is defined ONLY if the number of rows in A is equal to the number of columns in B

d. Matrix product ABAB is defined ONLY if the number of columns in A is equal to the number of rows in B

e. Provided that the product of ABAB is defined, the resulting matrix is of order nrows(A)ncols(B)nrows(A)ncols(B)

f. (AB)T=BTAT(AB)T=BTAT provided the corresponding products exist

g. (AB)1=A1B1(AB)1=A1B1 provided the corresponding products and inverses exist